From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from lists1p.gnu.org (lists1p.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-ECDSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 30EE3606A337 for ; Mon, 26 Oct 2026 06:25:07 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key, unprotected) header.d=redhat.com header.i=@redhat.com header.a=rsa-sha256 header.s=mimecast20190719 header.b=GOHThYp3 Received: from localhost ([::1] helo=lists1p.gnu.org) by lists1p.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1xLE8e-0005im-Vz; Mon, 26 Oct 2026 02:24:57 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists1p.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1xLE8d-0005hu-8N for qemu-devel@nongnu.org; Mon, 26 Oct 2026 02:24:55 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.129.124]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1xLE8b-00055P-Fv for qemu-devel@nongnu.org; Mon, 26 Oct 2026 02:24:54 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1792995891; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=92mhBjYA1LDuRae1rTnlIToVflITHf5NEuqr4jj3w+g=; b=GOHThYp3LocSu9m1mv4dOL52DqFdcV6JW41xtE47/S1MDPd3Q8Z/L0f8yh2SQWWMiRo+7T QQvuyZFWicemtQZXOqiF3hLxQL1+XCdlLZT18ucMHMJQDRKnyFgJbrzFdsUajKOTBzMSl/ 05wCK9de06NKGimNXZgl4w/Ml+HukMg= Received: from mx-prod-mc-08.mail-002.prod.us-west-2.aws.redhat.com (ec2-35-165-154-97.us-west-2.compute.amazonaws.com [35.165.154.97]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-387-MmCNoCjGPRCuYPi7mM1_ow-1; Mon, 26 Oct 2026 02:24:50 -0400 X-MC-Unique: MmCNoCjGPRCuYPi7mM1_ow-1 X-Mimecast-MFC-AGG-ID: MmCNoCjGPRCuYPi7mM1_ow_1792995889 Received: from mx-prod-int-05.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-05.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.17]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mx-prod-mc-08.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 082771800842; Mon, 26 Oct 2026 06:24:49 +0000 (UTC) Received: from blackfin.pond.sub.org (unknown [10.44.22.2]) by mx-prod-int-05.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 949D8195607F; Mon, 26 Oct 2026 06:24:48 +0000 (UTC) Received: by blackfin.pond.sub.org (Postfix, from userid 1000) id 1988F21E6A04; Mon, 26 Oct 2026 07:24:46 +0100 (CET) From: Markus Armbruster To: Hanna Czenczek Cc: qemu-block@nongnu.org, qemu-devel@nongnu.org, Kevin Wolf , John Snow , "Denis V . Lunev" , Eric Blake , Stefan Hajnoczi , Paolo Bonzini Subject: Re: [PATCH v2 02/12] qapi/block: Add IoAccountingOperation enum In-Reply-To: <4b4bd465-6e37-4db6-9680-ef346beb1244@redhat.com> (Hanna Czenczek's message of "Fri, 23 Oct 2026 16:30:22 +0200") References: <20261019182028.45305-1-hreitz@redhat.com> <20261019182028.45305-3-hreitz@redhat.com> <87y0bssyie.fsf@pond.sub.org> <87v76tgdg3.fsf@pond.sub.org> <4b4bd465-6e37-4db6-9680-ef346beb1244@redhat.com> Date: Mon, 26 Oct 2026 07:24:46 +0100 Message-ID: <87o6ch6ksx.fsf@pond.sub.org> User-Agent: Gnus/5.13 (Gnus v5.13) X-Archived-By: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable X-Scanned-By: MIMEDefang 3.0 on 10.30.177.17 Received-SPF: pass client-ip=170.10.129.124; envelope-from=armbru@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -30 X-Spam_score: -3.1 X-Spam_bar: --- X-Spam_report: (-3.1 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.339, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_LOW=-0.7, SPF_HELO_PASS=-0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: qemu development List-Archive: List-Post: List-Help: List-Subscribe: , Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org X-Spam-Status: No, score=-17.6 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_PASS, SPF_PASS,USER_AGENT_SANE_1 autolearn=ham autolearn_force=no version=4.0.1 X-Spam-Checker-Version: SpamAssassin 4.0.1 (2024-03-26) on aws-us-west-2-korg-listserv-alma10-1 Hanna Czenczek writes: > On 23.10.26 08:04, Markus Armbruster wrote: >> Hanna Czenczek writes: >> >>> On 20.10.26 07:59, Markus Armbruster wrote: >>>> Hanna Czenczek writes: >>>> >>>>> This enum gives more information than IoOperationType (which is used = for >>>>> the rerror/werror distinction) to identify operation types for block >>>>> accounting. >>>>> >>>>> Signed-off-by: Hanna Czenczek >>>>> --- >>>>> qapi/block.json | 20 ++++++++++++++++++++ >>>>> 1 file changed, 20 insertions(+) >>>>> >>>>> diff --git a/qapi/block.json b/qapi/block.json >>>>> index 0a88d405a26..8f4a71733c1 100644 >>>>> --- a/qapi/block.json >>>>> +++ b/qapi/block.json >>>>> @@ -629,3 +629,23 @@ >>>>> 'command': 'str' }, >>>>> 'features': [ 'unstable' ], >>>>> 'allow-preconfig': true } >>>>> + >>>>> +## >>>>> +# @IoAccountingOperation: >>>>> +# >>>>> +# I/O operation types as they are tracked by block accounting. >>>> Can we have a link to suitable docs on block accounting? >>> >>> Which do you have in mind? >> >> Hey, I asked first! > > :) > >> Two ideas to find candidates: >> >> 1. How is IoAccountingOperation going to be used? >> >> I can see events BLOCK_IO_DELAY and BLOCK_IO_DONE. Documentation >> there calls it "disk operation" in the event description and "I/O >> operation" in the argument description. Not a peep about >> "accounting". Might "tracked by block accounting" be about >> implementation? Or asked differently: why would the user care about >> block accounting here? > > Good question, the user presumably indeed won=E2=80=99t care. It is only = going to be used for those two events, so maybe it makes most sense to merg= e those three patches (`IoAccountingOperation`, `BLOCK_IO_DELAY`, `BLOCK_IO= _DONE`), so I can immediately refer to those events instead of accounting. You could also add the enum without a reference, then add references as you go. Not sure whether pointing that out in the enum's commit message would be advisable. > (The internal reasoning is that I don=E2=80=99t want this to deviate from= the existing accounting too much, so that maybe the accounting code can la= ter be switched to use the same request boundaries as this series introduce= s, and then switch its enum over to this QAPI variant. But absolutely not r= elevant to users, correct.) > >> 2. Assuming "block accounting" is actually relevant for the user: what >> are the QMP interfaces related to it? > > The best is probably the `BlockDeviceStats` keys for the different latenc= y histograms, which could be a map of this new enum to histograms instead= =E2=80=A6 But given the above, probably best to just drop this. Makes sense to me. Thanks! [...]